Despite calls for the identification of early risk factors for the development of chronic health conditions, there has been little longitudinal research on biomarkers of health that has been conducted in persons younger than 25 years of age. In addition, there is only a minimal understanding of how biological indices of early risk for adult health develop among adolescents with Latin American and Asian backgrounds, the two fastest rising ethnic groups in the United States, who are at differential risk for adverse health outcomes as compared to European Americans. An understanding of these processes is necessary for the development of ethnically and culturally relevant prevention efforts. We propose a 3-wave longitudinal study of adolescents and their caregivers from Mexican, Chinese and European backgrounds in order to assess the impact of daily experience on biological indicators of early risk for adult health. Our focus on daily experience stems from the need to identify the mechanisms by which global social factors identified in demographic surveys, such as lower education and income, play themselves out in individuals' daily lives. Daily experiences such as social conflict, excessive demands, emotional distress, threat, and sleep behaviors have been shown to be linked to both global risk factors and multiple biological indices of health risk among adults. The project will include both intensive behavioral assessments and detailed biological markers of health risk from both adolescents and their parents in order to address the following specific aims: (1) describe the development during adolescence of biological indices of early risk for adult health; (2) assess the role of daily experience in the development of early health risk; (3) examine the existence of ethnic disparities in early health risk; and (4) explore the role of potential protective factors in the development of early health risk. Approximately 540 pairs of adolescents and primary caregivers (180 from each ethnic group) will be assessed when the adolescents are approximately 15-16, 17-18, and 19-20 years of age. Each year, both adolescents and caregivers will participate in interviews that include measures of global social factors such as socioeconomic background and potential protective factors such as social connectedness. Participants will report daily experiences using a nightly diary checklist for 9 consecutive days. Salivary cortisol will be obtained at 4 time points each day for 4 of these days in order to analyze HPA activity, and participants will wear wrist actigraphs for the same 4 days to measure objective sleep behaviors. Blood pressure, BMI, and waist/hip ratio will be assessed, and dried blood spots will be obtained for the assessment of c-reactive-protein (CRP), cholesterol, and high density lipoproteins (HDL). Finally, peripheral blood samples will be provided by a subsample of 120 families for the assessment of plasma interleukin-6 (IL-6), a pro-inflammatory cytokine, and for gene expression analyses of molecular signaling pathways driving inflammatory biology.